ICHTHYOLOGY. 



255 



Clnssifica- ized by a peculiar hollow behind the gill-opening, which commu- 



tion — lla- nicates with the gills through an aperture, and lodges an accessory 



lacopteri. gill that has cartilaginous supports. The intestinal canal is very 



. ^ ■ long, being doubled upon itself many times, and in the interior of 



the oesophagus tliere is a complete spiral valve, of numerous turns, 



and with fringed edges, which have been observed in no other genus. 



Pancreatic caeca numerous. Air-bladder double, communicating 



with the cesophagug. Upper half of the mouth formed partly by 



the premaxillaries, partly by the maxiUaries. General aspect that 



of a t'oregonus. Species eight. 



Genus II. OoNOUHYNCnus, Gronov. {Rhynchana, TAich.) Body 

 elongated, with a slenderly conical head, ending in an acute snout, 

 which has a small median barbel beneath. Dorsal and anal fins 

 opposite, very far back ; long scaly processes in the axils of the 

 pectorals and ventrals ; branchiostegal membrane uniting with the 

 surface of the throat, and leaving merely a vertical slit for a gill- 

 opening. IJranchiostegals four j lips fringed and lobed. Scales 

 small, pectinated on the edge by a row of long and strong teeth. 

 Pharyngeal teeth cylindrical, truncated ; pyloric caeca six to nine; 

 no air-bladder. Two species. 



Family XVI — ALEPOCEPHALID^, Valenc. 



This family consists of a single species, of which M. Valenciennes 

 says ** the genus Alepoc^pkalus is separated from all others, and forms 

 the type of a peculiar family.' The upper jaw is that of the Pikes 

 {£sox), with an alimentary canal like that of the Clupeoids, and a 

 spiral valve in the rectum like Amia, but with many pancreatic 

 caeca and no air-bladder, whereas Amia and Chi>ocentrus have re- 

 markable air-bladders and no pancreatic CKca. No denticulations 

 on the belly like those of the Clupeoids. Body compressed, rounded 

 beneath ; long scalele?s head. Short premaxillaries bearing teeth, 

 forming the upper half of the mouth ; toothless maxiUaries lying 

 behind them ; palatine and mandibular teeth small. Siphonal sto- 

 mach with numerous pancreatic caeca ; spiral valve in the rectum. 

 One species. 



Genus I. Alepocephahis, Risso. 



CYPEINOIDS. 



This large family is a very natural one, but the great 

 conformity of structure exhibited by its very numerous 

 species is a source of difficulty to ichthyologists who have 

 attempted to divide it into genera, and other subordinate 

 groups. It is wholly a fresh-water family, and among the 

 least carnivorous in the class of fishes. 



Fig. 

 Cyprinus carpio, 



Ci/prinus carpio, the common Carp. This well-known 

 fiih Is of an olive-green, yellowish beneath, having the 

 anal and dorsal spines strong and denticulated, and the 

 barbels short ; the pharyngeal teeth are flat and striated 

 on the crown. It is a native of the central countries of 

 Europe ; but, owing to its value as an article of food, it 

 was early distributed by human agency over the whole of 

 that Continent. The ease with which it can be transported 

 from one place to another, and its speedy growth and pro- 

 pagation in ponds and artificial reservoirs, afforded great faci- 

 lities for its rapid dispersion. The year 1614 is assigned as 

 the date of its first introduction into England ; but it was na- 

 turalized in Germany and Sweden nearly half a century be- 

 fore that period. It delights in tranquil waters, preferring 

 such as have a muddy bottom, and the surface partially 



shaded with plants. Its food consists of the larvae of aqua- Classifica- 

 tic insects, minute Testacea, worms, and the tender blades tion— Ma- 

 and shoots of plants. The leaves of lettuce, and other '"^P'*'"- 

 succulent plants of a similar kind, are said to be particu- ^"^/^^ 

 larly agreeable to tliem, and to fatten them sooner than 

 any other food. Although the Carp eats with "reat vora- 

 city when its supply of aliment is abundant — to such a de- 

 gree, indeed, as sometimes to produce indigestion, which 

 occasionally proves fatal — it can subsist for an astonishini-- 

 length of time without nourishment. In the winter, when 

 the Carps assemble in great numbers, and bury themselves 

 among the mud and the roots of plants, they often remain 

 for many months without eating. They can also be 

 preserved alive ftjr a considerable length of time out of 

 the water, especially if care be taken to moisten them oc- 

 casionally as they become dry. Advantage is often taken 

 of this circumstance to transport them alive, by packino- 

 them among damp herbage, or wet linen ; and the opera" 

 tion is said to be unattended with, any risk to the animal 

 especially if the precaution be taken to |)ut a piece of breatl 

 in its mouth steeped in brandy ! In a similar way, the 

 Dutch preserve them by suspending them from the roof of 

 a damp apartment in a bag-net filled witji moss, which is 

 continually kept moist, and they are fed with veo-etables 

 and bread steeped in milk — a mode of treatment by wiiich 

 they are not only kept alive, but actually thrive and fatten. 



The fecundity of these fishes is very great, and their 

 numbers consequently would soon become excessive, but 

 for the many enemies by which their spawn is destroyed. 

 No fewer than 700,000 eggs have been found in the ovaria 

 of a single Carp, and that too by no means an individual of 

 the largest size. Their growth is very rajjid, more so per- 

 haps than that of any other fresh-water fish, and the size 

 which they sometimes attain is very considerable. In cer- 

 tain lakes in Germany and Prussia, individuals are occa- 

 sionally taken weighing thirty or forty pounds ; and Pallas 

 relates that they occur in the Volga five feet in Jeno-th 

 and even of greater weight than the examples just alluded' 

 to. The largest of which we have any account is tha 

 mentioned by Bloch, taken near Frankfbrt-on-the-Oder 

 which weighed seventy pounds, and measured nearly nine 

 feet in length. M. Valenciennes commends the small 

 figure of the Carp in Mr Yarrell's British Fishes, as beino- 

 the very best representation of the fish that he had seen. " 



Cyprinus auratus (Gold Fish). This beautiful species, 

 the most brilliantly adorned of all our fresh-water fishes 

 and scarcely sur|)assed even by the more richly ornamented 

 inhabitants of the ocean, is well known to be a native of 

 China, although it is now domesticated, so to speak, in 

 almost every country, both of the old and new world. 

 Like the Carp, it has the dorsal and anal spines denticu- 

 lated. When young it is of a blackish colour, and it gra- 

 dually acquires the fine golden red by which it is charac- 

 terized ; but some examples are of a silvery hue, aud 

 others are variegated with three different shades of colour. 

 Like most other animals that have been long estrano-fd 

 from their natural habits, aud subjected to artificial influ- 

 ences, this species presents a great many varieties, extend- 

 ing even to some important parts of structure. Individuals 

 occur without a dorsal, others with a very large one, others 

 with the caudal greatly enlarged, and divided into three or 

 four lobes ; and in some instances the eyes are enormously 

 dilated. The Golden Carp is said to have been ori"inally 

 confined to a lake near the mountain Tsienkin", m the 

 province of The-kiang, in China, about N. Lat. 30. It 

 was first brought to England in 1691, but was very scarce 

 till 1728, when a considerable number were imported, and 

 they soon became generally known. They do not flourish 

 in rivers and open ponds, not, however, because such places 

 are uncongenial to them, but because they are exposed to 

 many enemies, against which they have no means of de- 



